For ENG-6153, disable fadvise DONTNEED by default because it seems to make performance worse for Volt even if it helps other applications
For ENG-6153, add a helper method for spinning on a ReentrantLock
For ENG-6153, make it possible to set the number of spins on a lock including disabling spinning
Unrelated, remove pointless spinning that doesn't actually spin
For ENG-6513, add back a proxy method for taking from a queue with spinning. It's off by default as it was before

I tested a low concurrency scenario where spinning would provide the most benefit.

I found that with power governing on performance there was a throughput benefit, but 99.9 percentile went from 160 microseconds to 350 microseconds. I don't have a lot of execution units so I was probably over subscribed.

With power governing in on-demand the difference was huge and spinning was very beneficial.

Spinning is definitely not the right default policy because when you get it wrong or are oversubscribe the spinning kills you.
Merge pull request #1333 from VoltDB/ENG-6153-2

Eng 6153 2